Topical formulations containing phthalocyanine photosensitizers

1. A topical formulation comprising:

(a) a Zn-phthalocyanine derivative as a photosensitizing agent;

(b) diethylene glycol monoalkyl ether as a cutaneous permeation promoter contained in amounts of 3-35% w/w,

(c) a solvent selected from the group consisting of propylene glycol and polyethylene glycol;

(d) optionally a cutaneous permeation co-promoter selected from the group consisting of EtOH and iPrOH;

(e) a viscous agent selected from the group consisting of hydroxypropyl cellulose (HPC), hydroxymethylpropylcellulose (HMPC), polyvinyl alcohol (PVA), carboxymethylcellulose (CMC);

wherein said Zn-phthalocyanine derivative (a) is of formula (I)

wherein

n=0,1 and m=0,1,2 where when n=0 then m=0,1; when n=1 then m=0,2;

R is

2. The composition according to claim 1 , in the form of a non-aqueous transparent gel.

3. The composition according to claim 1 , characterized in that it is free of preservatives, stabilizers and other permeation promoters including in particular Tea Tree Oil (TTO), (±)-α-bisabolol (BIS) and isopropyl myristate (MYR).

4. The composition according to claim 1 , having a viscosity between 25 and 190000 cP.

5. The composition according to claim 1 , in which

the photosensitizer (a) is contained in amounts 0.050-0.500% w/w;

the diethylene glycol monoalkyl ether (b) is contained in amounts of 3-35% w/w;

the solvent (c) is contained in sufficient amounts to complete the 100% w/w composition;

the co-promoter (d) is contained in amounts 0-15% w/w;

the viscous agent (e) is contained in amounts 0.05-3% w/w.

6. The composition according to claim 1 , wherein the photosensitizer (a) is a compound of formula (I) wherein:

n=0, m=0 and

R, in position 1 or 2, is

or

n=1, m=0 and

R, in positions 1,4 or 2,3, is

or

n=0, m=1 and

R, in positions 1,8 (11),15 (18),22 (25) or 2,9 (10) 16 (17),23 (24), is

or

n=1, m=2 and

R, in positions 2,3,9,10,16,17,23,24, is

7. The composition according to claim 1 , wherein the photosensitizer (a) is the compound 1,8 (11), 15 (18),22 (25)-Tetrakis [3-(N,N,N-trimethylammonium) phenoxy] zinc phthalocyaninate (II) tetrachloride (RLP068/C1).

8. The composition according to claim 7 consisting of:

(a)

RLP068/Cl

0.1-0.3%

w/w

(b)

diethylene glycol monoethyl ether

5.0-10.0%

w/w

(c)

propylene glycol

q.s to 100%

w/w

(d)

EtOH

0-10.0%

w/w

(e)

hydroxypropyl cellulose

0.1-1.5%

w/w

9. A method for photodynamic therapy of skin or mucosal affections and for the simulation of repair and scarring process, said method comprising administering the composition according to claim 1 to a subject in need thereof.

10. The method according to claim 9 a simultaneous irradiation with a red light, for the localized topical treatment of skin infections of microbial origin from Gram (+), Gram (−) pathogens, yeasts, fungi and protozoa.

11. The composition according to claim 4 , wherein the viscosity is 25-65 cP.

12. The composition according to claim 4 , wherein the viscosity is 50000-190000 cP.